This study may answer or shed considerable light on four questions of great interest to the Institute and to all those involved in heart research. 1. Is angiography a reliable and useful tool for the evaluation of coronary artery disease? Can changes on angiography be read reliably enough to serve as an endpoint for scientific studies or important clinical decisions? 2. Can we significantly decrease the incidence of M.I. or death without any additional new treatments or medications? 3. Will lowering cholesterol slow down, stop, or reverse the progression of coronary artery disease? 4. Which populations of Type II patients would appear to do well on standard therapy and which do poorly. BIBLIOGRAPHIC REFERENCES: Belmaker, R.H., Pollin, W., Jenkins, C.D., and Brensike, J.F.: Coronary prone behavior pattern in a sample of Type II hypercholesteremic patients. J. Psychosomatic Research 20: 591-594, 1976.